Collapsible tube



Aprilv 12 1927.

` K. KIEFER GOLLAPSIBLE TUBE Filed Sept. 21. 1923 Fig. 1. Fig". Z.

Inventor Patented Apr. 12, 1927.

UANITEn STATES" KARL KIEFER, 0F CINCINNATI, OHIO.

" coLLArsIBLE TUBE.

' application med september 21, 192s. serial No. genova.

My invention relatesV to collapsible tube containers such as are used for holding pastes, creams and similar substances, to be I squeezed out through a neck at one end of .the tube; the opposite end being left open tube is squeezed, .even when the neck is closed, so that there will be no accidental disruption of this closed end of the tube. Heretofore, this closed end has been reinforced, usually, by some kind of clip, or by a stiffer piece of'material folded' with the tube walls', or by a solder, or other added element, to insure against the accidental opening just alluded to.

The object of my invention is to eiect a self-sustaini which will e ectively resist opening under. the circumstances above described, without the use of any additional piece or substance, and which will permit of rapid formation, preferably bythe use of automatic apparatus, whereby' these closures may be eiected with minimum expense. A further object is to provide suchia closure with the requisite neatness of appearance. Other objects will appear in the course of the ensuing description. p

I attain these objects by the device illustrated, for example, in the accompanying drawing, in which- Figure 1 is a side elevation of a collapsible tube embodying my invention; v Fig. 2 is'a side'elevation opposite to that seen 1n Fig. 1;

Fig. 3 isan enlarged partial perspective view of the tube, the view corresponding to that `of Fig. l.;

Fig. 4 is a partial erspective view of the tube, inverted as w en bein filled, and with the end flattened after lling, ready for the first stage of the closing operation; Fig. 5 similarly illustrates this tube upon completion of the first stage of the operation' 6 similarly illustrates this tube upon Ycompletion of the second stage of the operation;

Fig. 7 similarly illustrates this tube durclosure of this end of the tube ing an intermediate of the operation Fig. 8 is a partial cross-section, much enlarged, on a plane corresponding to the line 8-8 of Fig. 3; and

part ofthe third stage Fig. k9 is -a. 4vsimilar sectionlilllstrating modification of myV invention.

The collapsible tube 1 is of the usual well known construction, comprising the body 2 of soft metal, such as .a lead or tin alloy, ofA

ver thin sheet formed into a seamless tube' an having secured in one end the top 3 of similarv metal, having a threaded neckvon 'I which is screwed the cap 4 which is re- 'movedto allow escape of the contents when the body 2 is squeezed or contracted. Thesey tubes are supplied of circular cross-section from their tops 3 entirely to their opposite ends 5 (Fig. 4) which are vleft open for insertion ofl the contents while the tubes are inverted.

As illustrated in Figs. 4, 5 and 6, the initial stages of vformation of the closure according to my invention are similar to the operations heretofore performed `on such tubes. The'tube havingbeen filled to within a short distanceof the open end 5, this end is attened as seen in Fig. 4 until the two opposite sides 6 and 7 of this end lie closely together from one corner 8 to the other' in straight 'parallel lines. Then these sides 6 and 7 are folded on va transverse line represented by .the broken line A in Fig. 4,- over in the direction of the .arrow there shown, until the two portions of the outer surface of the side 6 lie closely together, as illustrated in Fig. 5, forming arounded edge9 and corners 10. Then the thus folded sides 6 and 7 are again foldedin the same direction as indicated by the arrow in Fig. 5, on a second transverse line B just .below the down turned end 5, so that the outer surface ofv the opposite side 7 now lies in against the outer surface of the side 6 with the end 5 up under the turn of the fold and the round- 4 down turned edge 9A and at the corners 8 i up in the fold. Such provisions are inconvenient, especially involvingV complication in conjunction with rapid automatic filling and closing of these tubes, as is desirable in large output of preparations packed in such tubes.

repeated foldsds suilicientv to unfold them 'and allow escape of the, contents at this end of the tube. I dispense with the use of such clips, soldering lor the like, and avoid the use of any additional piece or substance,

, yet effect a closure which I find effectively resists opening, even though the tube be squeezed without removing the .cap 4; continued squeezing of the tube resulting in bursting; of the unfolded body part of thel tube before failure of the closure.

This is accomplished by folding the seam formed as above described in direction opposite to that of the repeated .folds just made, so that this last folding will involve bothof the previously formed folds. Ilind that this is best accomplished .by folding diagonally or obliquely along lines repre? sented by the broken lines C* in Fig. 6, in reverse direction as indicated by the arrows in that view; these lines of folding extending from each end of the seam at a point slightly below -the down turned corner 10, upward toward the middle of the seam, `but not quite meeting at the middle,le`aving the seam unchanged in a short'` middle region 13. i This operation is seen partly completed in Fig.v 7; it being completed when the triangular corner parts have been folded down tightly against the outer surface of the side 7, upon which the closure4 will appear as shown in Figs. 1, 2 and 3, and as illustrated in cross-section in Fig. 8. Thus there is a double folding in one direction, straightl across the tube, and oblique folding in reverse directionof the double folds, so that. the double folds lie against one side of the tube in the middle region 13 and triangular triple folds lie against the opposite side of the'tube from this middle region out to both edges, with thel four thicknesses of metal of the double fold bent around the meeting sides 6 and 7 in the regions` 14: extending for some distance in each direction from the middle region 13.' Therefore, it is necessary for the pressure inside the tube toiovercome the stiffness of the two sides 6 and 7 at their second fold which formed the edge 9, and in addition to this to` overcome the stiffl ness of the fou-r thicknesses bent around this edgerfor a distance exceeding one-half the width of the closure.

In the modification illustrated Fig.2 9,

the final oblique folding will be understood to be the same as was described above,.but

previusly to this the flattened together sides 6 and 7 have been folded three' times' entirely across the tube. That is, after the closure Some additional securing of( -these end parts is necessary, because the pressure of the contents against the simple has reached the stage illustrated in Fig. 6, the material is folded down once more enti-rely across just below the edge 9, forming a new rounded edge 15; and then the-triple folds are folded obliquely in reverse direction, bringing the edge lobliquely along the side 7, with the edge 11 lying across the middle region of the side 6 and extending across to the opposite side asdid the edge 11 in the double-folded example. Thus, there are triple folds at one side in the middle, and quadruple folds, triangual-rl in shape, against the oppositeside, with six thicknesses of metal bent around 'the meeting sides 6 and 7, so lthat the pressure must overcome the stiffness of the two bent sides 6 and 7 and of the six thicknesses bent around as described.

g Iireitherl example, thisarrangement will not result in excessive bulk, nor will the folding of the numerous thicknesses be difficult, as would appear from the lexaggerated cross-sections of Figs. 8 and 9, because thel metal of the tubesis very thin and soft, so that it can -be Abent very sharply, and either example will appear substantially as shown in Figs. 1 and 2. All of the, folds may be madeby suitableautomatically operating mechanism, veryrapidly, neatly and uniformly throughout practically the enti-re area of the seam, with the folds pressed very flat, so that'the thickness of the closure is not noticeably thicker than the immediately adjacent unfolded sides of the tube, which'sides, as is well known, diverge rapidly fromthe closure, taking the approxi mately cylindrical yform a relatively short distance from the closure.

Other modifications of my invention may What I claim as new andn desire to secure by Letters Patent is:

1. A collapsible tube having an end'seam conslsting solely of the tube walls attened togetherl and sharply folded transversely,-

with opposite corner yparts of the transversely folded walls sharply folded obliquely toward each other, .whereby the thus folded walls are in' intimate contact with eachother throughout substantially .the entire area-of the seam, so. that the seani, due 'tosaid intimate contactand said sharp folds, is selfsustaining. l

2. A collapsible tube having an end seam consisting solely of the tube walls flattened togetherl and sharply folded transversely,

or in other respects, and: have somewhat specifically mate Contact andy said sharp folds, is self-v with opposite corner parts of the transversely folded Walls sharply folded obliquely toward each other in reverse direction to the transverse fold, whereby thethus folded Walls are in intimate contact with each other throughout substantially the entire area ofthe seam, so that the seam, due to said intisustaining.

3. A collapsible tube having a self-sustaining closure consisting solely of intimately sharp folds whioh cross each other.

4. A. collapsible tube having a self-sustaining closure consisting solely of intimately contacting portions of the tube walls having oppositely directed sharp folds which cross each other.

contacting portions of the tube walls having KARL KiEFER. 

